cj0022
Joined: 08 Jun 2008
Posts: 1
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| PIC18F2550 USB problem |
 Posted: Sun Jun 08, 2008 9:21 am |
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Hey Im new to PIC18f2550 and Im doing a project to use control 5 LEDs output from PIC28F2550 thru PC interface. My friend provide me an example codes I think probably from the internet. I'm having problem interpreting the code, I'm wondering if any of you can explain? and why there are two codes used for this application?
| Code: |
#IFNDEF __USB_DESCRIPTORS__
#DEFINE __USB_DESCRIPTORS__
#include <usb.h>
//////////////////////////////////////////////////////////////////
///
/// start config descriptor
/// right now we only support one configuration descriptor.
/// the config, interface, class, and endpoint goes into this array.
///
//////////////////////////////////////////////////////////////////
#DEFINE USB_TOTAL_CONFIG_LEN 32 //config+interface+class+endpoint
//configuration descriptor
char const USB_CONFIG_DESC[] = {
//config_descriptor for config index 1
USB_DESC_CONFIG_LEN, //length of descriptor size
USB_DESC_CONFIG_TYPE, //constant CONFIGURATION (0x02)
USB_TOTAL_CONFIG_LEN,0, //size of all data returned for this config
1, //number of interfaces this device supports
0x01, //identifier for this configuration. (IF we had more than one configurations)
0x00, //index of string descriptor for this configuration
0xC0, //bit 6=1 if self powered, bit 5=1 if supports remote wakeup (we don't), bits 0-4 reserved and bit7=1
0x32, //maximum bus power required (maximum milliamperes/2) (0x32 = 100mA)
//interface descriptor 0 alt 0
USB_DESC_INTERFACE_LEN, //length of descriptor
USB_DESC_INTERFACE_TYPE, //constant INTERFACE (0x04)
0x00, //number defining this interface (IF we had more than one interface)
0x00, //alternate setting
2, //number of endpoints, not counting endpoint 0.
0xFF, //class code, FF = vendor defined
0xFF, //subclass code, FF = vendor
0xFF, //protocol code, FF = vendor
0x00, //index of string descriptor for interface
//endpoint descriptor
USB_DESC_ENDPOINT_LEN, //length of descriptor
USB_DESC_ENDPOINT_TYPE, //constant ENDPOINT (0x05)
0x81, //endpoint number and direction (0x81 = EP1 IN)
0x02, //transfer type supported (0 is control, 1 is iso, 2 is bulk, 3 is interrupt)
USB_EP1_TX_SIZE,0x00, //maximum packet size supported
0x01, //polling interval in ms. (for interrupt transfers ONLY)
//endpoint descriptor
USB_DESC_ENDPOINT_LEN, //length of descriptor
USB_DESC_ENDPOINT_TYPE, //constant ENDPOINT (0x05)
0x01, //endpoint number and direction (0x01 = EP1 OUT)
0x02, //transfer type supported (0 is control, 1 is iso, 2 is bulk, 3 is interrupt)
USB_EP1_RX_SIZE,0x00, //maximum packet size supported
0x01, //polling interval in ms. (for interrupt transfers ONLY)
};
//****** BEGIN CONFIG DESCRIPTOR LOOKUP TABLES ********
//since we can't make pointers to constants in certain pic16s, this is an offset table to find
// a specific descriptor in the above table.
//NOTE: DO TO A LIMITATION OF THE CCS CODE, ALL HID INTERFACES MUST START AT 0 AND BE SEQUENTIAL
// FOR EXAMPLE, IF YOU HAVE 2 HID INTERFACES THEY MUST BE INTERFACE 0 AND INTERFACE 1
#define USB_NUM_HID_INTERFACES 0
//the maximum number of interfaces seen on any config
//for example, if config 1 has 1 interface and config 2 has 2 interfaces you must define this as 2
#define USB_MAX_NUM_INTERFACES 1
//define how many interfaces there are per config. [0] is the first config, etc.
const char USB_NUM_INTERFACES[USB_NUM_CONFIGURATIONS]={1};
#if (sizeof(USB_CONFIG_DESC) != USB_TOTAL_CONFIG_LEN)
#error USB_TOTAL_CONFIG_LEN not defined correctly
#endif
//////////////////////////////////////////////////////////////////
///
/// start device descriptors
///
//////////////////////////////////////////////////////////////////
//device descriptor
char const USB_DEVICE_DESC[] ={
USB_DESC_DEVICE_LEN, //the length of this report
0x01, //constant DEVICE (0x01)
0x10,0x01, //usb version in bcd
0x00, //class code (if 0, interface defines class. FF is vendor defined)
0x00, //subclass code
0x00, //protocol code
USB_MAX_EP0_PACKET_LENGTH, //max packet size for endpoint 0. (SLOW SPEED SPECIFIES 8)
0xD8,0x04, //vendor id (0x04D8 is Microchip)
0x11,0x00, //product id, me gusta el 11 ;)
0x01,0x00, //device release number
0x01, //index of string description of manufacturer. therefore we point to string_1 array (see below)
0x02, //index of string descriptor of the product
0x00, //index of string descriptor of serial number
USB_NUM_CONFIGURATIONS //number of possible configurations
};
//////////////////////////////////////////////////////////////////
///
/// start string descriptors
/// String 0 is a special language string, and must be defined. People in U.S.A. can leave this alone.
///
/// You must define the length else get_next_string_character() will not see the string
/// Current code only supports 10 strings (0 thru 9)
///
//////////////////////////////////////////////////////////////////
//the offset of the starting location of each string.
//offset[0] is the start of string 0, offset[1] is the start of string 1, etc.
const char USB_STRING_DESC_OFFSET[]={0,4,12};
#define USB_STRING_DESC_COUNT sizeof(USB_STRING_DESC_OFFSET)
char const USB_STRING_DESC[]={
//string 0
4, //length of string index
USB_DESC_STRING_TYPE, //descriptor type 0x03 (STRING)
0x09,0x04, //Microsoft Defined for US-English
//string 1 --> la compañia del producto ???
8, //length of string index
USB_DESC_STRING_TYPE, //descriptor type 0x03 (STRING)
'O',0,
'E',0,
'M',0,
//string 2 --> nombre del dispositivo
22, //length of string index
USB_DESC_STRING_TYPE, //descriptor type 0x03 (STRING)
'O',0,
'E',0,
'M',0,
' ',0,
'P',0,
'i',0,
'c',0,
'U',0,
'S',0,
'B',0
};
#ENDIF
#include <18F2550.h>
#fuses HSPLL,NOWDT,NOPROTECT,NOLVP,NODEBUG,USBDIV,PLL3,CPUDIV1,VREGEN
#use delay(clock=48000000)
#define USB_HID_DEVICE FALSE
#define USB_EP1_TX_ENABLE USB_ENABLE_BULK
#define USB_EP1_RX_ENABLE USB_ENABLE_BULK
#define USB_EP1_TX_SIZE 1
#define USB_EP1_RX_SIZE 3
#include <pic18_usb.h>
#include <PicUSB.h>
#include <usb.c>
#define LEDV PIN_B6
#define LEDR PIN_B7
#define LED_ON output_high
#define LED_OFF output_low
#define modo recibe[0]
#define param1 recibe[1]
#define param2 recibe[2]
#define resultado envia[0]
void main(void) {
int8 recibe[3];
int8 envia[1];
LED_OFF(LEDV);
LED_ON(LEDR);
usb_init();
usb_task();
usb_wait_for_enumeration();
// LED_ON(PIN_A0);
LED_OFF(LEDR);
LED_ON(LEDV);
SET_TRIS_A( 0xFF);
// LED_ON(PIN_B0);
while (TRUE)
{
if(usb_enumerated())
{
if (usb_kbhit(1))
{
usb_get_packet(1, recibe, 3);
if (modo == 0 || modo == 1)
{
if (INPUT_STATE(PIN_A1)& INPUT_STATE(PIN_A2))
{
resultado =3;
usb_put_packet(1, envia, 1, USB_DTS_TOGGLE);
}
if (!INPUT_STATE(PIN_A1) & INPUT_STATE(PIN_A2))
{
resultado =2;
usb_put_packet(1, envia, 1, USB_DTS_TOGGLE);
}
}
}
}
}
}
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